In the world, nothing’s like the World. Colossal, 12 years old, this 12-deck international floating home features golf, billiards, tennis, movies, poker games, lectures, classes, medics, spa, swimming, library, pingpong, five restaurants. It does everything but chew your edamame for you. Forget faint of heart.

On the World, the only concern is faint of wallet.

Residents buy — all cash — their own apartment. Some with a $1 million yearly maintenance. Heady, rich, 300 staff for 200 owners-at-sea, and there’s a waiting list. Most have a back story: a retired multimillionaire, a country’s Excellency.

A guest, I hopped aboard while it took on fuel. Seems Taipei-Keelung is cheaper than filling up your BMW on Montauk Highway. Taiwan, amid its Buddhist Ghost Festival to honor their ancestors, was sunny, hot, congested, bikes, motorcycles everywhere. Like home — except for a dumpling place so popular that the shortest lunch wait was 80 minutes.

It’s becoming Westernized. Ask about the subway, they refer you to McDonald’s.

Sailing the pacific Pacific 3,000 miles to Japan, specialists taught the how-tos. Tipping, no. Bowing, yes. If dipping into a communal bowl, reverse chopsticks. Vegetarian Confucius, who invented them 2,000 years ago, decreed the thick end that doesn’t touch your lips does the dipping. Never stick them straight up in your rice bowl. It’s an obeisance to the dead.

Big surprise was its big international fashion outlet. Gucci, Etro, Kors, Armani, Ferragamo, Ralph Lauren, Vivienne Westwood at 80 percent off. Woodbury, Asian style. Also worth a round trip on United is the area’s natural longevity. Not being a repeat visitor to downtown Okinawa, my surprise was that here 900 citizens live to beyond 100.

Overnight was in a heavenly local health spa. Ritual tea ceremony, tatami mats, futon beds, bare feet. Even if you don’t live to 100, with their seaweed, salt fish, tofu breakfasts, it feels that long.

In Amami Oshima — “Oshima,” as in Hiroshima, means “island” — a private land tour’s costly. Guides are imported from the mainland. Instead, I figured I’d nap in my cabin until a friend informed me: “The guide and car cost $2,000. Like it or not, you’re coming along, even if you sleep in the parking lot.”

The World’s two month summer sojourn, ending in Russia’s Sea of Okhotsk, stopped in Kagoshima, whose volcano erupted last week in an 800-meter plume. Located on seismic faults and Earth’s “Ring of Fire,” we’re talking 1,500 earthquakes yearly with 10 percent of the globe’s volcanoes.

Final stop for me, Nagasaki.

Nagasaki. Where none can forget 1945. This Aug. 9, its remaining survivors and thousands of mourners gathered in reverential silence to mark the 69th anniversary at exactly 11:02 a.m., when the 10,000-pound, 11-foot atomic bomb hit.

It was destined for the city of Kokura. Bad weather intervened and the target became Nagasaki.

Today the rebuilt city features colorful carp swimming lazily in the canal, the 1634 Spectacles Bridge built by a Chinese Zen priest, the Glover Mansion made famous as the home of Puccini’s “Madame Butterfly,” plus there’s trams, noodle shops, gondolas and a ropeway up the 11,000-foot mountain Inasayama.

There’s also the Atomic Bomb Museum, Peace Park, ground zero monument and WW2 history in films, photos, statues, artifacts. One particular wall lists the war’s precise progression. It begins with May 1943. No mention of Dec. 7, 1941. It lacks any sign of Pearl Harbor. Its message of devastation and heartbreak does, however, deliver a message: Do not harm the United States of America.

Aug. 15 the war ended.

And so is my journey. We’re now docked. The harbor, calm. The night, tranquil. Top deck, aft, the World offers heavenly Bali beds right out of House Beautiful. It’s sleeping outdoors under the stars . . . Sayonara . . .